Wworking on improving the tool

internal/datasource/epics/discovery_test.go

@@ -0,0 +1,82 @@
+package epics_test
+
+import (
+	"context"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/uopi/goca/proto"
+	"github.com/uopi/goca/testca"
+	"github.com/uopi/uopi/internal/datasource/epics"
+)
+
+func TestDiscovery_EnvironmentVariables(t *testing.T) {
+	// 1. Setup a fake CA server.
+	srv, err := testca.New([]testca.PVSpec{
+		{Name: "DISCO:PV", DBFType: proto.DBFDouble, Count: 1, Value: 123.45},
+	})
+	if err != nil {
+		t.Fatalf("testca.New: %v", err)
+	}
+	defer srv.Close()
+
+	// 2. Set the environment variable to point to this server.
+	os.Setenv("EPICS_CA_ADDR_LIST", srv.UDPAddr())
+	os.Setenv("EPICS_CA_AUTO_ADDR_LIST", "NO")
+	defer os.Unsetenv("EPICS_CA_ADDR_LIST")
+	defer os.Unsetenv("EPICS_CA_AUTO_ADDR_LIST")
+
+	// 3. Create datasource with NO explicit address (should pick up from env).
+	ds := epics.New("", "", "", "", false, nil)
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	if err := ds.Connect(ctx); err != nil {
+		t.Fatalf("Connect: %v", err)
+	}
+
+	// 4. Verify discovery works.
+	meta, err := ds.GetMetadata(ctx, "DISCO:PV")
+	if err != nil {
+		t.Fatalf("GetMetadata failed (discovery failed): %v", err)
+	}
+	if meta.Name != "DISCO:PV" {
+		t.Errorf("got %q, want DISCO:PV", meta.Name)
+	}
+}
+
+func TestDiscovery_ConfigOverride(t *testing.T) {
+	// 1. Setup TWO fake CA servers.
+	srv1, _ := testca.New([]testca.PVSpec{{Name: "PV:1", DBFType: proto.DBFDouble, Value: 1.0}})
+	defer srv1.Close()
+	srv2, _ := testca.New([]testca.PVSpec{{Name: "PV:2", DBFType: proto.DBFDouble, Value: 2.0}})
+	defer srv2.Close()
+
+	// 2. Point env to srv1.
+	os.Setenv("EPICS_CA_ADDR_LIST", srv1.UDPAddr())
+	os.Setenv("EPICS_CA_AUTO_ADDR_LIST", "NO")
+	defer os.Unsetenv("EPICS_CA_ADDR_LIST")
+	defer os.Unsetenv("EPICS_CA_AUTO_ADDR_LIST")
+
+	// 3. Create datasource pointing explicitly to srv2 (should OVERRIDE env).
+	ds := epics.New(srv2.UDPAddr(), "", "", "", false, nil)
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := ds.Connect(ctx); err != nil {
+		t.Fatalf("Connect: %v", err)
+	}
+
+	// 4. PV from srv2 should be found.
+	if _, err := ds.GetMetadata(ctx, "PV:2"); err != nil {
+		t.Errorf("PV:2 from config address not found: %v", err)
+	}
+
+	// 5. PV from srv1 should NOT be found (since AutoAddrList is disabled by config override).
+	ctx2, cancel2 := context.WithTimeout(context.Background(), 500*time.Millisecond)
+	defer cancel2()
+	if _, err := ds.GetMetadata(ctx2, "PV:1"); err == nil {
+		t.Error("PV:1 from env address was found, but config should have overridden it")
+	}
+}